would this work in a one gallon tank?

I wouldnt because the temp on this can go up to 79 degrees in a 10 gallon tank, for that reason i purchased a 10 watt for my 1 gallon tank and it keeps the tank at a perfect temp of 78. Check out the Marina C10 Submersible on Amazon for $10.00.

Description says "the ht30 is adjustable between 72 degrees f and 85 degrees f". ok, why does the one i received say not adjustable, preset at 78?

All of the HT Heaters are preset now. Unfortunately, this is an old image and old description of the former HT 55. The description seems to have been translated to the HT 100 as well. Tetra is working to correct these issues immediately. We appreciate your bringing it to our attention. If you need any other assistance, please contact the Tetra Consumer Relations Team at 1-800-526-0650.

Will this be okay in a 3 gallon betta bowl i'm making? if not any recomendations?

Yea i think so. I seriously look at this every day and im sooooooooooo glad i bought it. My betta looked so depressed before in his bowl because my house gets down to 60 degrees and his water was getting cold and now he is so happy his water stays 78 and he swims like a happy fish and has a lot of bubbles on top (means there happy). Its so crazy that warmer* water can make a fish soooo happy. This is a must. Yes buy it for a 3 gallon tank- i think it will work just fine and your fish will LOVE IT i promise! Let me know how it works out for you- because im so glad i got it!

Does it turns off automatically

When it reaches the right temp. it automatically shuts off. When the light on it is green, it's heating; when the light is red, it's off

100w Submersible Aquarium Heater For 10 30 Gallon Fish Tanks

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Fully operational. Shipping worldwide, on schedule.Duty & taxes paid at delivery

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€ 41.72

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Sold byAmazon CroatiaDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

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Description

🔥 Keep your tank perfectly cozy — because your fish deserve the best vibe!

VISUAL HEAT STATUS - Red and green indicator lights keep you effortlessly informed when heating is active or on standby.
POWERFUL EFFICIENT - 100-watt heating capacity perfectly tailored for 10-30 gallon tanks, ensuring rapid temperature stabilization.
DURABLE SAFE DESIGN - Heat- and shock-resistant glass tube with silicon carbide crystals for superior heat distribution and longevity.
EFFORTLESS INSTALLATION - Secure suction cup attachment means no hassle—just stick it inside your tank and enjoy peace of mind.
CONSISTENT COMFORT ALWAYS - Automatic thermostat maintains a steady 78°F for your aquatic friends’ ideal habitat.

The Tetra 100W Submersible Aquarium Heater is a UL-listed, durable heating solution designed for 10-30 gallon tanks. Featuring an automatic electronic thermostat that maintains a consistent 78°F, it prevents overheating and extends heater life. Dual-color indicator lights provide clear heating status, while a shock-resistant glass tube and silicon carbide crystals ensure efficient heat distribution. Easy to install with a secure suction cup, this heater is trusted by fish enthusiasts for reliable, hassle-free temperature control.

Specifications

ASIN	B000OQRJSG
ASIN	B000OQRJSG
Batteries	Product Specific batteries required.
Best Sellers Rank	#7,099 in Pet Supplies ( See Top 100 in Pet Supplies ) #11 in Aquarium Heaters
Brand Name	Tetra
Color	Black
Customer Reviews	4.4 4.4 out of 5 stars (16,788)
Date First Available	March 22, 2007
Department	Unisex-Adult
Global Trade Identification Number	00046798264460
Included Components	Aquaria 75026446: Tetra Submersible Aquarium Heater 100Wt
Item Type Name	Aquarium Heater
Item Weight	5.6 ounces
Item model number	26446
Manufacturer	Tetra
Manufacturer	Tetra
Material Type	Alloy Steel, Plastic
Model Number	26446
Number of Items	1
Part Number	AQ-26446
Product Dimensions	1.63 x 3.5 x 8.25 inches; 5.6 ounces
UPC	046798264460
Unit Count	1 Count
Warranty Description	See label
Wattage	100 watts

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€ 41.72

Duties & taxes included

In stock

Sold byAmazon CroatiaDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Croatia.

Secure transaction

Trustpilot

TrustScore 4.5 | 7,300+ reviews

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Received my product in pristine condition. Great service overall.

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